1. Field of the Invention
The present invention relates to washing machines and, more particularly, to a drawer-type washing machine provided with a washing tub unit designed to be opened or closed through a drawer-type moving action, thus allowing a user to easily put laundry into or take laundry out of the washing tub unit and being easily installed without being critically limited by vertical space above an installation area, and effectively washing a variety of laundries having different fabric characteristics and colors at the same time, in addition to efficiently washing a small quantity of laundry while conserving water, the present invention also relating to a process of washing laundry using such a washing machine.
2. Description of the Prior Art
FIG. 1 is a sectional view, showing the construction of the conventional upright washing machine.
As shown in the drawing, the conventional upright washing machine has a housing 2, which forms the exterior of the washing machine and is provided with an openable cover 1 at its top opening. A washing tub unit 5 is set within the housing 2, and consists of two tubs: an outer tub 3 and a perforated inner tub 4. The outer tub 3 contains washing water therein, while the perforated inner tub 4 is rotatably and concentrically set within the outer tub 3, and carries out both a washing operation and a spin-drying operation for laundry contained therein. A drive unit 6 is installed at a position under the outer tub 3 of the washing tub unit 5 within the bottom portion of the housing 2, and rotates the inner tub 4 at predetermined speeds. A plurality of suspension rods 7 support the outer tub 3 within the housing 2 while performing a damping function of attenuating operational vibrations of the washing tub unit 5 during an operation of the washing machine.
However, such a conventional upright washing machine is problematic in that it forces a user to put laundry into or take laundry out of the inner tub of the washing tub unit through the top opening of the housing after opening the top cover, thus being inconvenient to the user.
In addition, the upright washing machine has one washing tub unit, and so it forces a user to sort the laundries into several groups in accordance with different fabric characteristics and colors of the laundries prior to separately washing the laundry groups through two or more operation cycles, thus undesirably lengthening the washing time, in addition to excessively consuming water while washing the laundries.
Another problem experienced by the conventional upright washing machine resides in that it is necessary to secure sufficiently large vertical space above the top of the washing machine so as to allow a user to put laundry into or take laundry out of the washing tub unit through the top opening without being interfered by surrounding fixtures. The upright washing machine is thus critically limited in the vertical space above its installation area.
Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and an object of the present invention is to provide a drawer-type washing machine, of which the washing tub unit is contained in a cabinet designed to be drawn forward and pushed backward in the same manner as that of a conventional drawer, thus allowing a user to easily put laundry into or take laundry out of the washing tub unit.
Another object of the present invention is to provide a drawer-type washing machine, which has a plurality of washing tub units, thus allowing a user to simultaneously and separately wash several groups of laundries sorted in accordance with their fabric characteristics and colors, and which thus saves time during a washing process and is improved in its washing effect.
A further object of the present invention is to provide a drawer-type washing machine, which has an attractive appearance, in addition to being easily installed on a desired area without being critically limited by the vertical space above the area.
Still another object of the present invention is to provide a drawer-type washing machine, which effectively performs a washing process while conserving water, and reduces the amount of waste water, thus being less likely to cause environmental pollution, particularly, water pollution.
Still another object of the present invention is to provide a drawer-type washing machine, which is designed to automatically discharge vapor from the interior of the washing tub unit when pressure inside the washing tub unit is increased higher than a reference level, thus preventing unexpected breakage of the washing tub unit due to excessive pressure.
Still another object of the present invention is to provide a process of washing laundry using such a drawer-type washing machine.
In order to accomplish the above objects, the present invention provides a drawer-type washing machine, comprising: a housing opened at its front to form a cavity; a cabinet opened at its top and received in the cavity of the housing such that the cabinet is movable forward or backward relative to the housing; a washing tub unit consisting of an outer tub and an inner tub, and set within the cabinet, the washing tub unit containing washing water therein, and carrying out both a washing operation and a spin-drying operation for laundry contained therein; a drive unit installed at a position under the outer tub of the washing tub unit, and rotating the inner tub of the washing tub unit; a suspension unit used for supporting the washing tub unit within the cabinet while performing a damping function of attenuating operational vibrations of the washing tub unit; and a sliding unit provided at a movable junction of the housing and the cabinet for allowing a linear sliding movement of the cabinet relative to the housing.
In an embodiment, the interior of the housing is partitioned into two or more cavities by at least one partition wall, with two or more cabinets each having a washing tub unit therein and respectively received in the two or more cavities of the housing.
In such a case, the washing machine may have a first water feeding pipe used for feeding water to an upper washing tub unit received in the upper cabinet; a first water draining pipe used for draining water from the upper washing tub unit; a second water feeding pipe used for feeding water to a lower washing tub unit received in the lower cabinet; a second water draining pipe used for draining water from the lower washing tub unit; a first connection hose connecting the second water draining pipe to the first water feeding pipe; a second connection hose connecting the first water draining pipe to the second water feeding pipe; a first flow control device for selectively draining processed water from a rinsing operation of the upper washing tub unit to the atmosphere through the first water draining pipe or feeding the processed water from the upper washing tub unit to the lower washing tub unit through the second connection hose; and a second flow control device for selectively draining processed water from a rinsing operation of the lower washing tub unit to the atmosphere through the second water draining pipe or feeding the processed water from the lower washing tub unit to the upper washing tub unit through the first connection hose.
In another embodiment, the washing machine also has a pressure sensor used for sensing pressure inside the washing tub unit; a vapor exhaust port mounted to the top of the washing tub unit such that the port communicates with the interior of the washing tub unit, thus selectively discharging vapor from the washing tub unit to the atmosphere; a solenoid valve mounted to the vapor exhaust port and used for controlling the port; and a controller used for controlling the solenoid valve to open the vapor exhaust port when the pressure of the washing tub unit sensed by the pressure sensor is equal to or higher than a reference level.